*{
  margin:0;
  padding:0;
}
.wrapper {
  width:100%;
  height:100%;
  position: fixed;
  top:0;
  left:0;
  background-image: url('img/1.jpg');
  background-size: 100% 100%;
}

.btn{
  height:140px;
  width:170px;
  position:absolute;
  left:50px;
  background-image: url('img/startGame.png');
  background-size: 100% 100%;
  cursor: pointer;
}

.box{
  height:500px;
  width:500px;
  transform: perspective(800px) rotateX(45deg);
  margin:20px auto;
  border-top:1px solid #B25F27;
  border-left:1px solid #B25F27;
  box-shadow:  5px 5px 5px rgba(0,0,0,0.3);

  display:none;
}

.flagBox{
  position:absolute;
  top:50px;
  left:50%;
  width:200px;
  height:50px;
  margin-left:-100px;
  color:#333;
  font-size:20px;
  font-weight: bolder;
  display:none;
}
.alertBox{
  display:none;
  position:absolute;
  width:100%;
  height:100%;
  left:0;
  top:0;
  background-color: rgba(0,0,0,0.2);
}

.alertImg{
  width:600px;
  height:400px;
  background-size: 100% 100%;
  position:absolute;
  left:0;
  top:0;
  right:0;
  bottom:0;
  margin:auto;
  border-radius: 20px;
}

.close{
  position:absolute;
  right:0;
  top:0;
  height:40px;
  width:40px;
  background-image: url('img/closeBtn.png');
  background-size: 100% 100%;
  cursor: pointer;

}

.block{
  width:49px;
  height:49px;
  border-right:1px solid #B25F27;
  border-bottom:1px solid #B25F27;
  box-shadow: 0 0 4px #333 inset;
  background-image: url('img/cao.jpg');
  float: left;
}

.show{
  background-image: url('img/dilei.jpg');
  background-size: 100% 100%;
}

.num{
  background:#ECD0A1;
  font-size:18px;
  font-weight:bold;
  line-height: 49px;
  text-align: center;
}
.flag{
  background-image:url('img/hongqi.jpg');
  background-size:100% 100%;
}